Six fire engines and 35 firefighters and officers were called to a fire at a house in Beresford Avenue, Wembley.
The roof of a semi-detached house of two floors was destroyed and part of the roof of a semi-detached house converted into flats was damaged by the fire. There were no reports of any injuries.
The Brigade was called at 1353 and the fire was under control at 1617. Crews are likely to remain at the scene damping down into the evening. Fire crews from Park Royal, Wembley, Acton and Ealing fire stations attended.
The Brigade’s 999 Control Officers took 12 calls to the fire.
The cause of the fire is under investigation.